As for the broader picture, what we're seeing now started back in the 1980s when stockholders like T. Boone Pickens began demanding that corporations give them higher dividends instead of employees higher pay and benefits. In most cases, the old-style pension plans were replaced with 401(k)'s where both the employer and employee contributed to the employee's retirement investment, with the employer contributing a whole lot less than it used to.
A factor not often recognized is stricter financial auditing requirements. Beginning a couple of decades ago, companies were required to account more fully for the ongoing costs of defined-benefit plans, i.e. pensions (and of medical coverage for retirees), and were also required to disclose the assumed rate of return for their pension plans. In many cases, this sharply increased the costs of those plans as shown on balance sheets. This hit final-income schemes (such as basing the pension on the highest or final three years of income) particularly hard. Cash-balance pensions were less affected -- and were more portable for employees -- but still represented a cost. The only corporate costs for a defined-contribution plan (i.e. 401(k) and the like) are whatever corporate contributions are made plus whatever the company chips in for the costs of the plan.That was due predominantly to longer life spans and lots more job changing by the labor force.
401(k) plans originally started out as simple salary-deferral plans with no intention for use as retirement plans. But companies gradually shifted to them and they, along with old-style after-tax "thrift plans", evolved into what we have today.
A comparison with public-sector pension plans, still common for state and local governmental employees, can be instructive. (Federal employees are covered by a 401(k)-like defined-contribution plan with a small backup.) The audit requirements that apply to private-sector plans generally don't apply. Moreover, rate-of-return assumptions are less realistic, sometimes upwards of 7% or 8% per year. The plans have promised more than they can deliver. Consequently, this is why quite a few state and local governmental pension plans are having financial challenges. It's also why some of them are making very risky investments with private equity in the hopes of reaching or exceeding those rate-of-return assumptions, at the additional cost of poor liquidity. For 401(k) plans, the participants (employees) are solely responsible for figuring out how to get a reasonable rate of return. Many are not equipped to do so, which is a significant drawback to how retirement plans have evolved. But 401(k) plans aren't nearly as much of a drag on a balance sheet as defined-benefit plans, nor do companies incur nearly as much liability for results as long as reasonable investment options are provided.
iHeart actually does contribute to its employees' 401(k) accounts, though contributions were suspended in 2023 and 2024. They were resumed this year. The match is 2.5% of income to a maximum of $5,000 each year. I'd give that a C-minus grade -- I can't refine that further since I don't know whether iHeart covers recordkeeping and administrative costs, or whether some or all of those costs are charged to participants (which is a legal practice, though it chews into investment gains); nor do I know what kinds of investment options are available. So what's described here may or may not apply in specific circumstances, depending upon the provisions of a company's plan. Summary plan descriptions are informative but can be hard to find online.